This invention relates to a tool for removing wire coil screw thread inserts and, more particularly, to an improved extraction tool for tangless wire coil inserts.
Tools for the removal of wire coil inserts are well known. Generally, these tools have a tapered blade with a pair of knife edges which are driven into the inner diameter threads of the insert. However, when using these tools to extract an insert, the insert is permanently damaged. Further, to insure proper performance of these tools the blade must be placed into the hole so that one side of the blade is 1/4 turn from the trailing end of the insert. If the blade is placed in the hole other than 1/4 turn from the end of the insert, it will cause the end of the insert to dig into the parent material, thus damaging the threads in the tapped hole. In addition, the insert will back out with extreme difficulty. Still further, if the insert has been installed too deep, it is necessary to alter the taper of the tool blade so that it will not bite into the threads, countersink, or counterbore of the parent material.
Thus, there exists a need for an extraction tool for tangless wire coil inserts that solves the problems of the prior tools.